Gedde, Smith, Ifwarson, Viebke
Outstanding Applications # 1992 Eindhoven
Polyolefin pipes subjected to extensive hoop stresses fail in a ductile manner (stage I). At lower stresses failure is brittle and may in certain cases be preceded by degradation of the polymer (stage 111). Reviewed in this paper are the changes in polymer structure and antioxidant concentration profiles preceding the stage I11 failure of hot water polyolefin pipes. A diffusionlreaction model for the antioxidant loss is presented and applied to a few selected cases.